DE60030879T2 - METHOD AND DEVICE FOR NETWORK-CONTROLLED SUBSCRIBING IN A PACKAGED TELECOMMUNICATIONS NETWORK - Google Patents

Description

Territory of invention

The This invention relates generally to methods and systems to enable from handover of mobile units via Supply areas and in particular to procedures and systems to enable network-controlled handover in packet-switched cellular networks.

Background of the invention

Telecommunication systems, such as radiotelephone communication systems, require that a mobile unit, such as a laptop computer, a portable one Communication device, or another mobile device of one coverage area to another coverage area when the mobile unit is approaching from a service area moved to another, or if an overload occurs. A handover in the prior art is a jointly agreed transfer of a mobile device assigned radio resources and their control from one supply area to another supply area. Some digital wireless systems use mobile-based handover, where the mobile unit controls whether one handover to another Frequency or another code is performed. Further, for a cell reselection through the mobile device, these choices of which cell to select typically transparent to the radio resource network. Other conventional Handover operations can use a network-based control, for example, a Base station system determines the appropriate target cell and the handover the mobile unit controls. Such systems are for example in connection with circuit switching of digital cellular communication systems, such as the GSM system, known.

With the increased need for communication of real-time data, such as Real-time video and other data, for example, are modified circuit-switched digital cellular communication systems have been proposed. To the Example describes the general packet radio service (GPRS) network, in general in the European Standard GSM03.60 V6.2.0 described at the European Institute for telecommunication standards, F-06921 Sophia Antipolis Cedex, France, is a packet-switched digital cellular telecommunications system using a circuit-switched digital cellular communication system is used to one Packet switching and circuit switching of data (language, Video, and so on) to deliver. The packet data switching networks use a radio resource allocation, which is shared by mobile units. In contrast to arrange circuit switching telecommunication systems (for example TDMA-based systems) discrete parts of the bandwidth, the specific ones Be assigned to mobile units. For example, a specific TDMA timeslot for dedicated to a particular mobile unit. The GPRS network serves as an intermediary between the destination of the information and the mobile unit. Such However, packet-switched cellular networks typically do no mobility management features to disposal, which are sufficient to provide relatively seamless handovers of real-time connection oriented Communications available too put.

There are also For example, in the GPRS system there is no direct physical Connections between base station systems. In addition, the packet data switching network nodes typically unable to communicate information between base station systems respectively, because the SGSN only about aware of the BSSs being cared for by him, and not about others BSSs is aware. It is desirable the GPRS system and similar To modify the type of systems to network-controlled handover instead of enabling mobile-based handovers.

Separate Mobile units can require a plurality of radio resources. If, for example, the Mobile unit is a laptop computer, can radio resources in one package domain for one Number of software applications including, for example, a multimedia application, a modem communication application that runs on the computer, and Other radiotelephone application applications include sharing. The GPRS network uses a packet mode technique to data to transfer at high and low speed, and signaling. It tries to optimize the use of network and radio resources. A strict separation between the radio system and the network subsystem is maintained in an attempt to allow the network subsystem is reused with other radio access technologies.

However, such packet-switched cellular networks typically do not provide support for network-controlled handovers. For example, in GPSR network-based systems, it is the responsibility of the mobile unit to perform cell selection and routing and location area updates to the network. A problem may arise when the mobile moves from one cell to another because the flow of packets to the mobile can be interrupted until a successful cell clock has been completed. This will increase the time it takes to successfully complete the handover. In addition, if a mobile unit requires additional shared resources, namely shared time slots or shared codes, and the mobile unit requires an additional resource, for example, if a new software application requires an additional wireless connection, the mobile system may not has the information necessary to determine if the target cell has the appropriate resource requirements for the appropriate period of time. With real-time services in the packet domain, multimedia information, such as streaming video, can be undesirably interrupted during a mobile-unit-controlled handover. In addition, the base station system can not pass mobile units due to a certain congestion.

The Proposed improvements to the GPRS system also use one QoS table on a per cell basis, where packet data protocol contexts (PDP Packet data protocol) through a packet switching network element and not be entertained by the base station system. The The packet-switched network element is an SGSN. These PDP contexts can, for example on a per session basis, for a given mobile unit Source description data includes, for example, the bit rates for one view specific session, and other performance descriptors, such as for example, the acceptable delay for the given session. Several sessions will be for a given mobile device described. For example, a mobile unit may have a voice session, an internet web browsing session and include other sessions at the same time. The resource equipment information for one The given mobile device is switched by the packet data switching network to chat. Keeping this information on a per-cell basis however, by the SGSN limits the ability of the base station system to Perform functions related to traffic management. Therefore the serving GPRS support node (SGSN) has to do each time be informed if any given mobile unit into a Cell is located. This may affect the ability of the base station system to Perform functions related to traffic management, sensitive limit. At the moment, a handover of mobile devices is possible the BSS not independent be performed by the packet-switched network element.

Furthermore need the packet data switching network typically requests a packet supply and leads the packets to the appropriate base page control. That of the SGSN packet sent to a BSS includes addressing information under another mobile identifier (MID) and a cell identifier (CELLID) contains. Thus, the SGSN must be during a handover to lead mobile devices to cells, but he does not have the required handover information. The base page control the information passes to the specific cell through the Address information from the SGSN is displayed. The SGSN schedules Packets on a per cell basis and addresses packets to cells (in addition to mobile devices), making a base station system simple just need to know that it needs to perform the protocol translation, and know a timing when to send the information. It would be however desirable if a packet routing could be done by the BSS to one To reduce overhead of the SGSN. There is also a need that the BSS traffic management based on radio-related information performs, because the current GPRS system does not carry mobile devices in less congested Cells available provides.

A known technique for Network-based handover is based on digital cellular circuitry Switching systems, such as the GSM system used. However, such systems are not typically set up to Package switching information to enable a handover. Current network-based handoffs typically range only based on a signal strength indicator and a radio resource quality further. Known network-based Consider handover typically no quality of service on a per-mobile basis, which has been displayed. With packet switching systems, it is desirable to have a Having network-controlled handover that meets the needs considered by multiple users of shared radio resources. It would be desirable if such a system for example over the ability decreed move a mobile device to another coverage area, to allow another mobile device to improve its quality of service, For example, if a new mobile device has an additional Radio resource needed. Additionally allow known digital cellular communication systems using packet data exchange, while handover no renegotiation of service quality changes during the Call. Consequently, a mobile unit is not allowed to use it during the Add handover resources or reduce resources.

The EP 0898438 discloses a method and system for controlling a radio communication network and a radio network controller. In connection with a connection setup, a radio network anchor control is selected over which User information flows throughout the duration of the connection. When the connection is forwarded to a base station belonging to another radio network controller, the user information is routed to travel via the anchor controller to the active radio network controller.

The GB 2 332 340 discloses a method for facilitating a handover wherein a mobile station transmits radio linkage reports in an encapsulated form to a service node to enable the service node to make handover decisions instead of or in addition to the normal handover decisions made at the BSC.

The US 5278892 discloses a packet-switched CDMA communication network in which soft handoffs can occur without a change in the call processing unit handling the call, such that a single call processing unit handles the call.

According to one The first aspect of the invention is a wireless network handover control device according to claim 1 available posed.

According to one second aspect of the invention is a digital wireless system according to claim 10 available put that over has a packet-switched data network element that works with at least a first and a second base station system communicates.

According to one Third aspect of the invention is a method for wireless network handover control according to claim 19 provided.

Accordingly There is a need for a device and method that Network-controlled handover in a packet-switched digital wireless system allows.

Short description the drawings

1 FIG. 12 illustrates a block diagram of an example of a system employing network-controlled handovers in a packet-switched digital telecommunications system according to one embodiment of the invention [MSC stands for mobile switching center, we should find another expression for what is referred to as MSC in the figure].

2 FIG. 10 is a flowchart illustrating an example of a message exchange in the in 1 shown system according to an embodiment of the invention.

3 FIG. 10 is a block diagram illustrating an example of a base station system having handover control of shared resources in accordance with an embodiment of the invention. FIG.

4 FIG. 4 is a flowchart illustrating the operation of an example of the device of FIG 3 represents.

5 FIG. 10 is a flowchart illustrating a session structure according to an embodiment of the invention. FIG.

6 FIG. 10 is a flowchart illustrating a method of network controlled handover in a packet switched telecommunication system based on congestion determination according to an embodiment of the invention. FIG.

7 FIG. 10 is a flowchart illustrating an example of the method of network controlled handover in a packet switched telecommunication system based on determining what new shared resources are needed by a mobile unit, according to an embodiment of the invention.

Detailed description of the preferred embodiment

in the Generally, a method and apparatus for enabling control a network-controlled handover in a wireless network, the packet switching and a use of shared Resources, such as time slots, and a network element, such as a base station system, provides a handover of a mobile unit by providing packet routing for one Plurality of mobile units to a handover of at least one To enable mobile unit. The base station system sets a memory element, such as a database or other suitable storage that is stored Radio resource requirement data, such as PDP context information, contains on a per-mobile basis. By doing that the packet routing, the storage and maintenance of shared-use radio resource requirement data stored on the base station system level in a network, can Network-controlled handover without the control of the packet-switched Network element providing packets to the base station system, occur.

In one embodiment, a control device comprises a handover in a wireless network, such as that in a base station system or other suitable network A shared resource controller that is operable to track available shared resources, such as frequencies, time slots, codes, or other radio resources commonly used by mobile units, also includes packet handover -Control. The packet handover controller is in effective communication with the shared radio resource controller and provides packet routing of data packets received from the packet-switched network. The packet routing is modified such that the packet-switched network maintains a mobile for a base station system, and the control of shared radio resources, such as a BSS, receives estimates that the mobile-context identifier in the packet contains (e.g. Example Context ID), and the packet leads to the appropriate cell based on a context ID / cell reference table or some other mechanism. This is done on a per-mobile basis. The packets are routed to the BSS serving the mobile device. The addressing mechanism may be based on a network address, such as an IP address mapped to a context or flow identifier, or an identifier derived from an IP address or other suitable information. In addition, the disclosed method and apparatus include enabling resource allocation, release, creation, and deletion of packet data contexts at a destination base station system, or other network element, and a source base station system, or other network element. The system and method also handle the destination and source network elements to perform handovers for traffic management purposes independent of the packet-switched network.

In another embodiment stores a packet-switched data network element, such as an SGSN, or other suitable element, data, the base station system identification data for base station systems representing the packet switching data network element become. additionally Beyond that Data stored, the other packet-switched data network elements for others Base station systems present in such base station systems bordered by packet switching data network elements become. A packet-switched data network element then performs based on the stored base station system identification data and the stored packet switching data network element identification data, Messages to a suitable base station system or another Packet switching data network element.

1 provides an example of a digital wireless system 10 that is via a packet-switched network 11 has one or more packet-switched network elements 12 which is in effective communication with a radio resource network control element, such as a first base station system 14 with a handover control of shared resources, and a second base station system 16 with controlling a handover of shared resources. For illustrative purposes only, the invention will be described with reference to a GPRS system. However, it will be understood that the invention is applicable to any suitable wireless communication system having a packet switch. The packet-switched network element 12 can, if necessary, operate effectively with a Gateway GPRS (GGSN) support node 18 be linked. The packet-switched network element 12 can also, by a mobile switching center 22 and a transcoder 24 language encoded in a format suitable for transmission over radio (for example, full rate, half rate, adaptive multi-rate) translated into speech suitable for transmission over a public switched telephone network (PSTN) (eg A Law PCM) is suitable to a public telephone network 20 coupled to those skilled in the art. The packet-switched network element 12 For example, it may be an SGSN or any other suitable packet-switched network element.

The base station systems 14 and 16 are in this embodiment part of a radio telephone system, which is generally in 26 is shown. In general, a handover will find a mobile unit 28 from the first base station system 14 to the second base station system 16 instead, when the mobile unit 28 a coverage area boundary 30 crosses or comes close enough. The mobile unit 28 may be any suitable communication unit, software application, or other functional unit connected to a base station system via a wireless connection 32 communicated. The arrow 34 shows the direction of movement of the mobile unit 28 across an edge into a coverage area, for example from one cell to another cell.

As known to those skilled in the art, the gateway support node may be 18 (GGSN) suitably through a compound 36 with the SGSN 12 be connected. So is the packet switching network 11 through the connection 38 to the transcoder 24 coupled and the transco of 24 through the connection 40 to the MSC 22 coupled and the MSC 22 through the connection 42 to the PSTN 20 coupled.

The packet-switched network element 12 is through the connection 44 effective to the first base station system 14 coupled, wherein packetized data, such as real-time, audio, video, voice, data or other information, are communicated on a packetized basis. The second base station system 16 Having resources shared with a handover control is also through the connection 46 with the packet-switched network element 12 connected. If necessary, can also have a direct communication connection 48 between the first base station system 14 and the second base station system 16 be used.

The first base station system 14 Resources shared with a handover control receive packet-switched data from the packet-switched network element 12 about the connection 44 , The first base station system 14 represents the mobile unit 28 provide a base station system handover by providing packet routing for one or more mobile units to facilitate handover of the mobile unit from one cell to another. Accordingly, packet routing is performed by the base station system, as opposed to the packet-switched network. The BSS determines the cell of the mobile device for which any given packet is intended and then routes it to the appropriate cell for transmission. The BSS maintains a database of mobile devices on shared channels and maintains a table of which mobile devices (on a per context ID basis) are in which cells and routes the packet to the one based on the context ID in the packet suitable cell. Therefore, the SGSN does not need to accumulate or send the cell ID, but only needs to pass the correct packet to the right BSS, such as a look-up table, a context ID of a given mobile, and the associated BSS for that context Id identifies as determined by standard mobility requirement procedures. The first base station system 14 and the second base station system 16 have essentially identical components. Therefore, the following descriptions will be made with reference to the first base station system 14 performed; however, they are just as much on the second base station system 16 applicable.

It will open 2 With reference herein, a method for providing wireless network handover control to the system of FIG 1 generating a source base station system handover shared resource request to a destination base station system as in the block 200 shown. For illustrative purposes, and without being limited thereto, will be the first base station system 14 as the source base station and the second base station system 16 considered as the destination base station. The establishment of a signaling connection between the source and potential destination base station systems may be accomplished by using a physical connection, such as the direct communication link 48 , between the source BSS and the destination BSS, or through a logical connection that traverses one or more network elements, such as a BSS, SCSN, and GGSN. In this embodiment, the packet-switched network element becomes 12 considered to have a single packet switching network element, such as an SGSN. In this embodiment, the packet-switched network element stores 12 a table including, for example, data representing base station systems, together with base station system identification data for either such base stations transmitted by the SGSN (for example, the BSS 14 and 16 ) or for base station systems adjacent to one or more base station systems served by the SGSN. As such, the packet-switched network element stores 12 Data representing base station system identifications for base station systems served by the packet-switched data network element and storing data representing other packet-switched-data network element identification data, such as base-station systems adjacent to such base-station systems as used by the packet-switched network element 12 be supplied. Upon receiving a packet having a base station system identifier as the destination station from a source BSS over the connection 44 , routes the packet-switched network element 12 forward the packet to the destination BSS if it is a BSS in the table indicating that it serves the destination BSS. Otherwise, the packet switch network element will redirect 12 forward the packet to another suitable packet-switched data network element serving the destination BSS identified by the BSS identifier in the packet. The through the packet-switched network element 12 For example, the stored table may be in the form of a routing table used to determine whether the destination base station system is being serviced by the packet-switched data network element, and if not, the packet data protocol address (eg, an Internet Protocol address) of the packet-switched network element is serving the destination base station system , Alternatively, the direct communication connection 48 be used as a mechanism for direct base station-to-base station signaling for the purpose of handover.

Each base station system 14 and 16 resources shared with a handover control store radio resource requirement data on a per-mobile basis. For example, packet data protocol (PDP) contexts, as defined, for example, in GPRS Specification No. 03.60 v 6.2.0, are stored in a database or other suitable memory by the base station systems 14 and 16 can be accessed, stored on a per-mobile basis. Examples of PDP contexts for mobile devices can be found, for example, in GPRS Specification No. 03.60 v 6.2.0, page 81. The contexts are dynamically updated by the BSS as radio resource requirements change. The shared radio resource requirement data may also be stored, for example, on a per-group-of-a-mobile basis, for example, when mobile units are grouped into appropriate groups. Although the base station systems 14 and 16 It may be understood that a database may be stored at any suitable location for access by a suitable base station system. For example, the handover shared resource request may include a handover resource request message to another network handover controller, such as the first base station system 14 to the second base station system 16 , be. This query may be in the form of suitable CDMA-based handover control packets. The handover shared resource query may include data representing, for example, whether a destination base station system has the necessary available codes, time slots, and other resources to accommodate a mobile unit that will be passed from one cell to another. The handover shared resource query may take many forms, including, for example, a simple query, where the query is generated to contain data that is responded by the target base station system, thereby indicating the capability requested Support handover. Alternatively, an implied resource allocation query may be used that results in the current allocation of resources, which may be all or predetermined subsets of the active PDP context, to support the requested handover. In the case of a simple query, the source BSS determines the ideal target cell from a list of target cells being polled and initiates the handover procedure.

As in the block 202 shows the destination base station system, such as the second base station system 16 by evaluating a shared resource availability table, a handover shared resource response to the query back to the source BSS indicating, for example, whether it has appropriate shared resources. For example, the destination base station system may indicate whether shared resources, such as codes and time slots, are available for various mobile unit packets to be passed on. As in the block 204 As shown, after the handover shared resource response to the source base station system, the process includes 14 a generation, for example, by the source base station system 14 , a packet data protocol context override message for the packet-switched network element 12 , To perform a handover for any given mobile unit, the base station system should be aware of all the mobile unit's active packet data protocol contexts before it can initiate the handover process. The stored shared radio resource requirement data, also referred to as the PDP context information, may be obtained from any suitable source that owns the packet switching network element 12 comprising mobile unit, or any other suitable source. In the event that not all PDP contexts are successfully passed, the source BSS may repeat the polling process with a new set of potential targets, delay the handover attempt, or override or terminate one or more PDP contexts and with continue the handover. After the source BSS has received responses from a plurality of destination BSSs, the source BSS may determine the ideal destination cell to which the mobile unit may be forwarded. For example, the ideal target cell may be based on best conventional cell algorithms, and may additionally include whether all PDP contexts can be supported by the target BSS. After the ideal destination BSS has been identified by the source BSS, the source BSS notifies the ideal destination BSS and informs the destination BSS to reserve the required resources in anticipation of the handover.

As in the block 206 As shown, the source BSS generates a packet data protocol context override message sent to the packet-switched network element 12 is sent to indicate that all PDP contexts associated with the mobile unit should be placed in an override state. The packet-switched network element 12 buffers any downlink packet for an overriding PDP context until the PDP context is activated or after a predetermined time has elapsed. As in the block 208 the source BSS then generates one Handover command to the mobile unit to command the mobile unit to go to a specific destination cell. As in the block 210 The mobile unit then generates a handover access request and communicates the request to the destination BSS, as in the block 210 shown. As in the block 212 3, after detecting a handover from the mobile unit, the destination BSS generates a packet data protocol context de-activation message to the packet-switched network element 12 to the packet-switched network element 12 request to modify or reactivate the PDP context associated with the present mobile unit. The requested modifications may include one or more of the following modifications: modification of the cell, quality of service for one or more PDP contexts, deletion of a PDP context that can not be supported after the handover is completed, or any other suitable request of modifications. For example, the handover may only be applicable to a subset of the PDP contexts, resulting in the deletion of the remaining active PDP contexts. In addition, after detecting a handover from a mobile unit, the destination BSS informs the source BSS by providing a handover success message about the successful completion of the handover. Alternatively, the packet-switched network element 12 the source BSS, after modifying and activating the PDP context, indicating that the successful completion of the handover has occurred. Providing the handover success indication from the destination BSS to the packet-switched network element 12 and providing the handover success indicator from the packet-switched network element 12 to the source BSS is in the blocks 214 respectively 216 After the successful handover, the source BSS then releases all resources that have been allocated to the mobile unit. The resources associated with the mobile unit are typically released by the source BSS only after receiving notification of a successful handover from the destination BSS. This allows the mobile station to return to the source in the event of an unsuccessful handover attempt. Additionally, it will be appreciated that if communications are used between packet switching data elements, then the source SGSN may act as an anchor for all or some of the PDP contexts.

It will open 3 Referring to FIG. 1, an example of a network handover control device is included 300 a control of shared radio resources 302 , a packet handover control 304 with dynamic handover radio resource requirement data updating capabilities, an uplink / downlink packet router 306 and the memory 308 containing the shared radio resource requirement data 309 stored on a per serving mobile device basis. The network handover control device 300 For example, in the first base station system 14 and the second base station system 16 be included. The network handover control device 300 receives the packet data 310 from the packet-switched data network element via the connection 44 , The package data 310 include a context ID for each mobile. The network handover control device 300 puts the handover tax packages 312 which includes a cell ID to which the mobile device shall pass, the frequency, the code, the time slot, or any other suitable data allowing access by the mobile device. In addition, conventional traffic packages may also be provided by the network handover controller 300 be issued. The network handover control device 300 may be implemented using one or more appropriately programmed computers, processing systems, or any suitable combination of hardware, software, or firmware. The control of shared radio resources 302 is effective to track available shared radio resources for each mobile unit served by a base station system. The control of shared radio resources 302 For example, it may be a software program or a combination of hardware, software, and / or firmware that maintains, for example, a table of available shared resources, such as time slots, frequencies, codes, and any other suitable radio resources that may be used by a plurality of mobile units be shared on a package basis.

The packet handover control 304 provides mobile units that it services with packet routing of received data packets to enable handover of mobile units. By doing that the packet handover control 304 provides packet routing, packet routing is used by the packet-switched network element 12 emotional. An advantage of this arrangement is that the BSS can perform handovers without informing the SGSN. With regard to packet routing, the packet handover control knows 304 to which cell (if any) a given mobile device belongs and thus which packets have to be routed to which cell (the ID of the mobile device is located in the header of each packet).

Additionally updates the packet handover control 304 the shared resource requirement data 309 dynamic in the memory 308 for each mobile device stores when the resource requirement of a mobile device changes during the course of its activation. The radio resource requirement data may include, for example, the number of codes needed by a mobile device, the quality of service requirements of a mobile device, or any other suitable radio resource requirement data. To determine if the radio resource requirement data is to be updated, the packet handover control determines 304 whether changes due to a change in the traffic or changes in the resources available (e.g., increased or decreased radio resources), or by the mobile sending a message to the SGSN, indicate one or more PDP contexts for that mobile to update. Such is the network-based packet handover control 304 as a kind of PDP context manager. The packet handover control 304 may be implemented as a software program executed by a suitable processing unit. The packet handover control 304 generates the override and / or activation command data 318 indicating the activation or override of the radio resource requirement data 309 for a given mobile unit based on resource requirements of the mobile unit and the available shared resources of a BSS. For example, a field associated with a given PDP context for a given mobile device contains information indicating whether the PDP context has been overridden due to limited resource availability. The packet handover control 304 receives the radio resource requirement data 309 containing the override / activation information to dynamically update resources for mobile devices. The packet handover control 304 also generates the resource availability update data 322 to the control of shared radio resources 302 so that the control of shared radio resources 302 can update the state of available resources after the packet handover control 304 has determined which shared resources are available, in terms of those used by all mobiles being served. The control of shared radio resources 302 generates a resource availability 324 for the packet handover control 304 so that the packet handover control 304 can make a decision on whether the handover can be accommodated for a negotiation for additional resources. The packet handover control 304 also generates the mobile unit control data 326 and the router control data 328 ,

The mobile unit control data 326 become the packet router 306 where they are packetized for transmission to control a handover of the mobile unit. The mobile unit control data 326 include the handover tax packages 312 , As a part of the mobile unit control data 326 for the packet handover control 304 The mobile device provides information regarding the surrounding cell, such as SSI, bit error rates, and other suitable data used to determine if a handover should occur.

The packet handover control 304 generates the router control data 328 which may be packet data, for example, suitably through the packet handover control 304 have been addressed so that the packet data is passed to the appropriate cell where the desired mobile device is located.

Even though with reference to between-BSS-like handovers, such as those between BSS's the with different BSS's connected it is clear that the disclosed apparatus and method also applied to intra-BSS handover can be such as between two or more BTSs linked to a same BSS.

It will open 3 and 4 Referring to this, a flowchart ( 4 ) of an example of the operation of the network handover control device 300 shown, the device 300 Receive mobile device measurement report data in the form of packet data from the packet network to determine a signal strength indication from neighboring cells. This will be in the block 400 shown. As in the block 402 As shown, the device determines if there are alternative cells that can service the mobile device. As in the block 404 shown calculates the network handover control device 300 jointly-used resource requirement data 309 that in the store 308 stored for the given mobile device. As in the block 406 shown compares the packet handover control 304 for each target cell, the mobile radio resource requirement data with the shared-use packet resource availability data of a target cell to determine whether the target cell can accommodate the necessary shared resource requirements of the further-depleting mobile device. The network handover control device 300 may compare the mobile radio resource requirement data with shared-use packet resource availability data to a target cell on a static or a dynamic basis. For example, consider the network handover controller 300 on a static basis only currently allocated resources. The network handover control device 300 also leads the Ver on a dynamic basis, taking into account traffic requirements for given resources by other mobile units to determine whether mobile devices can be removed or added.

As in the block 408 shown prioritizes the packet handover control 304 Target handover cells using any suitable priority rules known to those skilled in the art. The process includes determining if the serving cell is the best cell, as in the block 410 shown. For example, if the serving cell has the highest C / I, if the serving cell needs the fewest contexts to override, or any other suitable criteria for the mobile. The best cell may also have a network perspective that considers both the traffic and the required or requested contexts of other users. The best cell can be from a system perspective, not just the individual mobile device perspective. If it is, there is no handover. However, if the serving cell is not the best cell, the process involves determining whether the available resources of the best cell are the same or adequate resources as those of the current cell for the mobile, as in the block 412 shown. If the available resources of the target cell are not the same as the available shared resources of the serving cell, the process includes, as in the block 414 shown negotiating with the mobile unit to change (add or reduce) resources for a new association. For example, if a mobile device is moving and a target cell can not accommodate all the software applications that require digital wireless communication, the base station system negotiates with the mobile unit to determine if an application can stop operating for a period of time, or alternatively if the target cell has additional resources that the mobile unit wants to use, the mobile unit is asked if additional resources can be used. Thus, the system negotiates allowable mobile device resources with a mobile device target cell network element intended for handover after target cell selection by either overriding at least a portion of a PDP context associated with a mobile device, disabling at least a portion of a PDP context. Context associated with a mobile device or reactivating at least a portion of an overdrafted PDP context associated with a mobile device.

As in the block 416 After the appropriate shared resources have been determined, the source base station system requests a selected destination cell to allocate the shared resources desired by the mobile. As in the block 418 As shown, the process includes sending handover command packets from the source to the mobile unit to inform the mobile unit. This is done, for example, by sending the command data 318 carried to the router. The router then updates the routing table data generated by the control of shared radio resources 302 to be controlled. The routing table update data 329 serve as a dynamic feedback to allow for dynamic updating of radio resource requirement data for mobile units. For example, inform when the packet handover control 304 determines that a radio resource will be used for a given PDP context, the routing table update data 329 the control of shared radio resources 302 about which radio resource is no longer (or now) available. As in the block 420 As shown, the process includes updating the radio resource requirement data 309 in the store 308 based on the negotiation. This is done by sending the resource availability update data 322 to the packet handover control 304 then carry out the radio resource requirement data 309 based on the routing table update data 329 updated.

Accordingly, the packet handover control determines 304 a most suitable mobile unit target cell based on stored radio resource requirement data. The packet handover control 304 negotiates allowable mobile unit resources with a destination cell network element, such as a base station system, for a mobile unit intended for handover after a destination cell selection, based on stored radio resource requirement data. As such, after an initial session has begun, a renegotiation of resources by network-controlled handover mechanisms may occur without the intervention of the packet-switched data network element 12 be enabled. The packet handover control 304 allocates radio resources of a mobile unit based on the stored radio resource requirement data 309 For example, another mobile device may need additional resources, a reshared mobile device may be denied a shared resource for the benefit of a mobile unit using the shared resource, or alternatively, the packet handover may include: control 304 Re-allocate radio resources to allow a mobile unit to obtain additional resources at the expense of another mobile unit that may be about to leave the target cell or that is at a lower priority level, or based on the type of information being communicated, such as real-time information versus not real time data. The reassignment of radio resources may be based on the resource requirement data of another mobile device within the cell or on the resource requirement of a mobile device outside the cell.

5 Figure 4 illustrates an example of an active session between a source network element and a mobile unit in accordance with an embodiment of the invention. As shown, the network element, such as a base station system, activates the session with the mobile unit as known to those skilled in the art and in the block 500 will be shown. As in the block 502 2, the base station system determines whether resources are available to the mobile unit based on the radio resource requirement data 309 stored by the packet-switched network or in the base station system for the given mobile device. When the resources are available, the system stores the resource requirement data 309 in the database, as in the block 504 shown. The base station system then allocates the shared memory resources as by the radio resource requirement data 309 provided, as in the block 506 shown. The base station then informs the mobile device that the required shared packet resources are allocated, as in the block 508 and the session is then continued to allow the mobile unit to communicate information packets.

6 FIG. 12 illustrates a flowchart showing a handover based on detected congestion by a base station system or by another suitable network element. FIG. As in the block 600 As shown, the process includes determining whether a congestion-based handover is needed for a mobile device. This is determined, for example, based on traffic density information accumulated by the BSS for each cell.

7 FIG. 12 illustrates a flowchart showing a handover according to an embodiment of the invention based on a determination of whether new resources are needed by a mobile unit. As in the block 700 As shown, the process includes determining whether new resources are needed by a mobile unit based on a request by a mobile unit for additional shared packet resources. This can be done, for example, when a new PDP context is activated for a mobile device and the current cell in which a mobile device is located does not have enough resources for that context and all the already active contexts.

As described, the packet handover controller generates and receives 304 Data representing, for example, a handover resource request message to another network handover controller, a handover resource reply message, a handover request, a packet data protocol context override message, and a packet data protocol context de-activation message, all of which are preferably packetized communications.

Although not in 3 shown where the network handover control device 300 Also located in another network element, such as an additional BSS, a second memory that can be accessed by the second network element also includes the dynamically updated radio resource requirement data 309 for a plurality of mobile units served by the network element, such as a base station system. Accordingly, the additional base station system further includes a handover controller having a shared radio resource control substantially similar to that described with reference to FIGS 3 is identical. Where multiple packet handoff controllers are used, they negotiate allowed mobile unit resources from a mobile unit intended for handover after destination cell selection based on the dynamically updated radio resource requirement data 309 and one of the stores new. In addition, the base station systems 14 and 16 Part of an RF digital communication network element that uses both packet switching formats and circuit switching formats to communicate data with a plurality of mobile units.

Accordingly, a guaranteed quality of service may be provided for all or a pre-negotiated set of active PDP contexts or shared radio resource requirement data upon completion of the handover. Since the handover is network controlled independent of the packet switching network element, minimal disruption in packet transmission reception may be allowed during the handover process. In addition, a handover may include a subset or superset of PDP contexts. Additionally, renegotiation of quality of service criteria during a handover may be provided to provide flexibility in improving service handling in response to For example, to allow congestion data, availability of shared resources, and other criteria. A faster handover may occur due to the minimal involvement of the packet-switched network element. Other advantages will also occur to those skilled in the art.

It It is clear to those skilled in the art the implementation of Other variations and modifications of the invention in its various Aspects come to mind and that the invention is not by the described specific embodiments is limited. It is therefore intended that the present invention any and all modifications, variations, or equivalents covering, to the extent of the underlying main principles which are disclosed and claimed herein.

Claims (29)

A handover control device for a wireless network, comprising: a shared radio resource control ( 302 ) working to track available shared resources; characterized in that the apparatus further comprises: a base station system (BSS) having a packet handover control (BSS); 304 ) in operative communication with the shared radio resource controller used to provide packet routing of received data packets to a plurality of mobile units; a memory operatively coupled to the packet handover controller ( 308 ) containing stored radio resource request data comprising PDP context information, and wherein the packet handover controller is operative to determine an appropriate target cell for the at least one mobile unit based on the stored radio resource request data and the contained PDP context information. Network handover control device according to claim 1, the memory storing the stored radio resource request data on a per-mobile unit basis. Network handover control device according to claim 1, where the packet handover control works to allow mobile unit resources with a target cell network element for a mobile unit, the for a Handover after a target cell selection is provided based to renegotiate the stored radio resource request data. Network handover control device according to claim 1, where the packet handover control works to radio resources at least one mobile unit based on the stored radio resource request data, reassigned to another mobile device. Network handover control device according to claim 1, where the packet handover control works to radio resources at least one mobile unit based on cell congestion data assign. Network handover control device according to claim 1, wherein the packet handover controller generates and receives data that represent at least one handover resource request message to another Network Handover Control Device, one Handover resource response message, a handover request, a packet data protocol context override message, or a packet data protocol context de-activation message. Network handover control device according to claim 1, wherein the shared resource control and the packet handover control Part of a digital RF communications network element working to both packet switching and circuit switching formats for communicating data with the plurality of mobile units to use. Network handover control device according to claim 1, which includes a packet router ready for packet handover control which is working to packets from a packet-switched network element to receive and provide handover control packages for a mobile unit. Network handover control device according to claim 1 where the shared radio resource control is working, to radio resource request data based on resource availability update data to update. A digital wireless system having a packet-switched data network element in operative communication with at least a first ( 14 ) and second ( 16 ) Base station system (BSS), characterized by: a first memory to which the first base station system ( 14 ), which contains dynamically updated radio resource request data for a plurality of mobile units serviced by the first BSS, and wherein the first BSS shared a first one Includes radio resource control that operates to keep track of available shared resources, and includes a first packet handover controller that is in operational communication with the shared radio resource controller that is operative to perform packet routing of received data packets for one To provide a plurality of mobile units; a second memory to which the second base station system ( 16 ), which includes dynamically updated radio resource request data for a plurality of mobile units served by the second BSS, and wherein the second base station system comprises a second shared radio resource controller and a second packet handover controller located in one is operable communication with the second shared radio resource controller that operates to provide packet routing of received data packets to a plurality of mobile units, the dynamically updated radio resource request data comprising PDP context information, and wherein the first and second packet handovers Control to determine a suitable mobile unit target cell based on the dynamically updated radio resource request data and the contained PDP information in the first or second memory. System according to claim 10, wherein the first and second packet handover controls operate, by permissible Mobile unit resources for a mobile unit designed for a handover is provided based on a target cell selection to dynamically updated radio resource request data in the first or second memory with a target cell network element renegotiate. System according to claim 10, wherein the first BSS operates to generate data containing a Handover toothed resource query for the second BSS, based on the dynamically updated radio resource requirement data, which are stored in the first memory, and wherein the second BSS works to generate data that has a handover resource response for the represent first BSS based on shared resource availability data the second BSS, and wherein the first BSS operates to generate data the one packet data protocol context override message, corresponding to a mobile unit passing on to the second BSS is for that Represent packet data switching network element, and wherein the second BSS operates to generate data representing a packet data protocol context de-activation for the Packet data switching network element in response to a successful Represent handover of the first BSS. System according to claim 10, with the first packet handover control works to allocate radio resources to at least one mobile unit based on the stored radio resource request data, which with a linked to another mobile unit are to reassign. System according to claim 10, with the first packet handover control works to allocate radio resources to at least one mobile unit based on Cell congestion data reassign. System according to claim 10, wherein the first and second base stations are part of a digital RF communications systems are both packet switching formats as well as circuit switching formats for communicating data used with the majority of mobile units. System according to claim 10, wherein the first BSS includes a first packet router that is operational coupled to the first packet handover control that works, to receive packets from the packet-switched data network element, and works to provide handover control packages for a mobile device put. System according to claim 16, wherein the second BSS comprises a second packet router, the operably coupled to the second packet handover controller that works to packets from the packet-switched data network element to receive, and works to handover control packages for a mobile Unit available to deliver. System according to claim 10, where the first shared resource control is working, to radio resource request data based on resource availability update data to update. A wireless network handover control method comprising the steps of: receiving, by a base station system ( 14 ) packet-switched data from a packet-switched data network element ( 11 ); characterized in that the method further comprises the steps of: providing, by the base station system, base station system controlled handover of a mobile unit ( 28 ) receiving the packet-switched data by providing packet routing for a plurality of mobile units; Tracking, by a shared radio resource control, available shared resources; Storing, for access by the base station system, radio resource request data where at the stored radio resource request data, PDP context information; Determining, by the base station system, an appropriate mobile unit target cell based on the stored radio resource request data and the containing PDP context information. Method according to claim 19 where the radio resource request data is on a per-mobile basis get saved. Method according to claim 19, the step of renegotiating allowed mobile resources with a mobile device target cell network element comprising for a Handover after a target cell selection is provided based on the stored radio resource request data. Method according to claim 19, the step of reallocating radio resources to at least comprising a mobile unit based on the one with another stored mobile unit linked Radio resource requirement data. Method according to claim 19, the step of reallocating radio resources to at least a mobile unit based on cell congestion data. Method according to claim 19, which includes the following steps: Create and receive messages that include at least: a handover resource request message to another network handover controller, a resource reply message, a handover request, a packet data protocol context override message, or a packet data protocol context re-activation message. Method according to claim 19, communicating, through the base station system, of data in both a packet switching format and a circuit switching format for communicating data with mobile units. Method according to claim Figure 19, providing a handover control packets for a mobile through the base station system Unit includes, based on the stored shared Radio resource requirement data. Method according to claim 19, wherein the step of renegotiating allowed mobile Resources with a target cell network element for a mobile unit, the for a Handover after a target cell selection is provided, an override at least part of a mobile unit-linked PDP context includes. Method according to claim 19, wherein the step of renegotiating allowed mobile Resources with a target cell network element for a mobile unit, the for a Handover after a target cell selection is provided, a deactivate at least part of a mobile unit-linked PDP context includes. Method according to claim 19, wherein the step of renegotiating allowed mobile Resources with a target cell network element for a mobile unit, the for a Handover after a target cell selection is provided, a reactivate at least part of a mobile unit linked out of power set PDP context includes.